Catheters for the introduction or removal of fluids may be located in various venous locations and cavities throughout the body for the introduction or removal of such fluids. Such catheterization may be performed by using a single catheter having multiple lumens. A typical example of a multiple lumen catheter is a dual lumen catheter in which a first lumen introduces fluids and a second lumen removes fluids. These catheters are very useful for procedures such as hemodialysis, wherein blood is removed from a patient through the first lumen for processing in a hemodialysis machine, and the processed blood is returned to the patient through the second lumen. Alternatively, multiple catheters, each having a single lumen, may be inserted in multiple locations in the patient, such as in each femoral vein.
Many such catheter assemblies are presently utilized that include extension tube assemblies at proximal ends of the lumens of multi-lumen catheters, and clamps are commonly used that allow manual actuation to clamp and unclamp the extension tubes to occlude fluid flow therethrough at selected times, such as during connection to and disconnection from tubing of hemodialysis machines. One particularly popular clamp is an in-line pinch clamp known as a Halkey-style or Roberts clamp, which has: a skeletal-like framework 62 defining an axially extending body portion having transverse distal and proximal end portions 64, 66; tube openings 68 through its transverse distal and proximal end portions 64, 66 through which the tubing 50 extends; a flexible latching arm 70 extending proximally from the distal end portion 64 thereof to a free end 72, and the transverse proximal end portion 66 of the clamp comprising a catch arm 74 extending to a free end upon which is defined a catch 76, for the latch arm free end 72 to become latched thereto; and cooperating clamping sections 78, 80 that impinge on the tubing 50 to occlude it when the clamp 60 is in its clamping state, one clamping section 78 being on the flexible arm 70 and the other being defined on the axially extending body portion, both intermediate the distal and proximal ends 64, 66. The latching arm 70 is adapted to be easily manipulated by hand between latching and unlatching conditions that correspond with clamping and unclamping states of the clamp 60. Such a clamp 60 would be maintained in the clamped state most of the time, that corresponds to all times other than when a practitioner is performing hemodialysis or infusion, or is withdrawing a blood sample.
Such a clamp in its latched and clamped state has a drawback in that the free end of the catch arm can snag on clothing, linens, tubing, wiring and other articles and snag and strain the tubing and the catheter, potentially harming the patient or damaging the catheter assembly. Even more problematic is that the catch arm free end can snag sufficiently to unlatch the latching arm resulting in unclamping of the clamp permitting blood to flow freely from the patient, causing great harm, especially when the patient is unattended in order for remedial action to be performed.
It is desired to provide a way of minimizing the possibility of the tubing clamp snagging or becoming inadvertently unclamped.